It is known that certain batteries, and in particular, those of the type mentioned above, are poor at withstanding deep discharges and overcharging, so it is necessary to take special precautions to prevent such events during use, especially when the batteries comprise cells that are connected in series.
For various known reasons, the individual cells making up a given battery do not all operate under exactly the same conditions, and they do not all age identically, so it is often not sufficient to monitor the operation of a battery solely on the basis of electrical measurements performed in operation from the end terminals thereof.
In particular, with batteries that include cells connected in series, the slightest differences that may exist initially between the cells tend to increase with operation to the detriment of the poorer cells such that their loss of performance gives rise more or less quickly to loss of performance in the other cells.
It is therefore known, both during charging and during discharging, to associate measurements performed cell by cell with the measurements already performed across the end terminals of a battery that is in operation in order to be able to take action on the battery as a function of the way in which each of its cells taken individually is, in fact, performing, and also as a function of the way in which the overall assembly constituted by all of said cells is performing as a whole. It is also known that the same operations can be performed on modules that are made up identically, each comprising the same number of cells selected from within a battery that includes a large number of cells.